Question: CY7C0852V BSDL and JTAG Questions: - What is wrong with the Pause-DR state? - How do you prevent going into the Pause-DR state? - What happens during JTAG testing when I enter Pause DR? - What happens to the CY7C0852V JTAG Chain in PAUSE-DR State?
Answer: The C7C0852V inserts an extra clock when it transitions from the PAUSE-DR state to the SHIFT-DR state. This is because the CY7C0852V "stutters" when making this state transition SHIFT-DR -> EXIT1-DR -> PAUSE-DR -> EXIT2-DR -> SHIFT-DR The bit stream should pick back up on the first falling TCK edge once back in SHIFT-DR. What happens is the first bit is clocked out twice, thereby adding a bit into the stream. This problem is duplicated in the SHIFT-IR -> EXIT1-IR -> PAUSE-IR -> EXIT2-IR -> SHIFT-IR state transistion. If you are using the PCI-100 pod, selecting the "gated" TCK under Hardware Setup should prevent the devices from going into a pause state. If you are using the older pc/at pod, there is no way to prevent entering the pause state.
